/Engine/Source/Editor/UnrealEd/Public/Tools/LegacyEdModeWidgetHelpers.h
Override CreateWidgetHelper function to return a SharedRef to the class you created in step 1.
class UBaseLegacyWidgetEdMode : public [UEdMode](API\Editor\UnrealEd\Tools\UEdMode), public [ILegacyEdModeWidgetInterface](API\Editor\UnrealEd\Tools\ILegacyEdModeWidgetInterface), public [ILegacyEdModeViewportInterface](API\Editor\UnrealEd\Tools\ILegacyEdModeViewportInterface)
TSharedPtr<FLe...
WidgetHelper